Propeller shaft bearing and support for model airplanes



R. T. DANIEL March 26, 1935.

PROPELLER SHAFT BEARING AND SUPPORT FOR MODEL AIRPLANES Original Fi led June 10, 1952 Patented Mar. 26, 1935 PROPELLER. SHAFT BEARING SUPPORT FOR MODEL AIRPLANES Raleigh T. DanieL Colorado Springs, 0010.

Application June 10, 1932; Se'rial No. 616,533 Renewed August 16, 1934 I 8 Claims. (Cl. LG- 50) This invention relates to an improved propeller shaft bearing and support for model, air-' planes, and has for its object the production of a. simple and eflicient mounting for the propeller shaft which is so constructed as to permit the propeller shaft to flex the required amount should the propeller strike a foreign object;

Another object of this inventionv is the production of a simple and eficient elastic anchorage and mounting for the propeller shaft of a model airplane which will flexibly support the propeller shaft in such a manner as to permit the bearing to provide a universal flexing action in the event the propeller should strike an object.

A still further object ofthisinvention is the production of a simple and efiicient bearing and mounting of a propeller shaft for a model air= plane which consists of-a minimum number of parts, which may be manufactured cheaply, and

-whichis efficient in operation.

With these and other objects in view, this invention consists in certain novel constructions, combinations and arrangements of parts as will be hereinafter more specifically described and claimed;

In the drawing:

Figure 1 is a side elevation of a motor stick showing the propeller bearing and, motor band associated therewith, the motor stick being adapted to be supported upon a model airplane in any suitable or desired manner as is the custom of the trade;

Figure 2 is an enlarged side elevation of the bearing and hanger associated with a portion of the motor stick, a portion of the propeller being shown in section; Figure 3 is a Figure 2;

Figure 4 is a 'sectiontak'en on line 44 of,

- Figure 2;

Figure 5 is a longitudinal sectional view tion with the present device.

By referring to the drawing, itwill be seen motor stick that 1 designates a conventional which carries at one end of the motor band the supporting hook 2 for engaging one end of the motor band 3. Secured to the forward end of the motor stick 1 and preferably to the underface thereof, is a sheet metal hanger memberi formed of a light metallic structure and having a rear-' wardly extending connecting finger 5, the hanger member 4 being adapted to be glued to the underface of the motor stick 1, and then wound or wrapped by means of the winding threads 6. It

should be understood, however, that the'hanger member 4 may be secured to the forward end of the motorstick 1 in any convenient or desired section taken on line 33 of' manner common to-"the trade, without departing from the spirit of theinvention. This hanger member 4 is provided with a front plate 7, which front plate is provided with a comparatively centrally located bearing receiving aperture 8 which is only of suiiicient size to permit the bushing 9 of the bearing plate 10 to'pass therethrough,

and properly flex to provide a universally flexing joint. 7

The bearing plate 10 is provided with the rearwardly extending bushing 9-and a forwardly ex-' tending bushing 11 through which extends the comparatively short propeller shaft 12 which propeller shaft 12 supports at its forward end the usual propeller 13 and is provided at its rear end with a motor band engaging hook 14, as shown.

This propeller shaft 12 is only of suflicient length to permit of a proper connection with the motor band 3, and is sumciently' short to allow a maximum swinging movement of the shaft without contact with the bottom face of the motor stick 1.

The bushing, 11 ispreferably provided with an annular flange 15for contact withthe bearing bead-16. The bearing plate 10 is preferably circular in shape and is adapted to normally snugly fit against the front face of the front plate '7, as is shown in Figure 2, to constitute a sturdy and eficient propeller shaftsupporting member.

An anchorage plate or ring 17 is mounted to fit flat upon the front face of the bearing plate 10,-

the bushing 11 projecting through the ring or I anchorage plate, as clearly shown in the drawing.

This anchorage plate 1'7 is provided with aplurality of, outwardly projecting and inturned tongues 18 formed preferablyv upon the periphery of the an-, chorage plate or ringl'l, these tongues, 18 extending' toward the propeller and away from the, hanger 4. .An elastic band 21 .of any suitable or desired structure is passed under and around these tongues 18 as shownin the drawing, and the hanger member 4 is provided-upon the side flanges 19 thereof with apertures 20 through which the elastic band 21 is threaded. The hanger member 4 is provided. with a flange 22 at the bottom thereof having an. aperture '23 formed therein, and a plurality of apertures 24 are formed in the front plate? of the hanger near. the top thereof, as shown 1 clearly in Figures '3'- and 6 of the drawing. In carrying out the proper elastic anchoring of the bearing and anchorage plate, the elastic band 21 is "threaded through the apertures 24 and then under one ofthe tongues 18,: the band-then extending u h one -of the apertures 20, and-B then under the next adjoining tongue18, then through the lower aperture 23,, and then under the next adjoining tongue 13, and then; through the opposite side aperture 20 and finally under,

the remaining tongue 18 when the. ends of the elastic band may be secured together, thereby providing an efficient elastic anchorage for the anchorage plate and bearing plate whereby the bearing platemay be normally held flatiagainst the front face of the ifrontplate '1, as shown in Figure 2, to normally support the propeller shaft 12 in proper alignment. Should, however, the propeller come in contact with a foreign object,

the bearing so constructedand designed'asabove' set forth, will permit of a proper and immediate planewill, strike its propeller j against some obthroughout "the plane.

flexing of the required amountto prevent injury to the propeller, the elastic anchorage providing a bearing which will be in thenature of an elas tic universal joint permitting the flexing of the bearing at any angle.

From the foregoing description, it will be seen that-a very simple and efficient flexible mounting for the propeller shaft has been produced which willbe cheap in structure and which will possess a minirnumweight as isnecessarily required in a device ofthis particular character. 7

It has long been recognized in thisparticular line of invention that the provision of a flexible mounting for the propeller is very essential. Since a model airplane flies without pilot control, it is liable to, and in nearly every flight the model airject and may even nose over while moving along the-ground. Hence, it is essentially. important that the' shaft be so mounted as to permit the same to flex.

It is well recognized that in the usual shaft hanger, the horizontal propeller thrust line is maintained only by reason of the rubber band motor which is attached to the shaft thereof, and that during operation the line of thrust will be continually changing, since the rubber unit when unwinding will not do so with perfect smoothnem. This will cause a yanking of the shaft in View of the factthat the horizontalalignment ofthelshaft isdependent upon themotor and the thrust line will be continually changing, and cause the propeller to'revolve in an eccentric cirole. iThe. propellerv efficiencyis in this manner cut:

down and often undesirable vibration is set up In my invention, however, I have provided for the propeller shaft a solid bearing prepared of turned brass whichis normally heldagainst the face'of the hanger by means of the rubber band anchorage 21 illustrated and described above, and in this way'the shaft is, under ordinary conditions, held in straight alignment and if some dearrangingforce is applied to the. propeller, such for instance,-.. as the strikingv of the propeller against: a foreign; object,r the elastic anchorage immediately allows the propeller to flex the required amount and thus prevent injury.

With, this structure described, I provide a smooth and true running propeller which, with a" proper design and selection of material, will also prove a verylight bearing arrangement. The

relativeshort: propeller shaft will also, as stated above, permit of a maximum swinging action contact 'with the motor stick. The provision of the'solid turned'bearing will greatly enhance the value of the device in maintaining the propeller in itstrue and proper position. V p

It" should be understood that certain detail changes in the mechanical structure may be employed without departing from the spirit of the invention, so long. asithese changes-fall within the soope of the appended claims.

Having described the invention, what is claimed as new:--

1. A bearing fora model airplane shaft comprising a hanger, said hanger having 'a'plurality of apertures formed therein, a bearing plate mounted upon said hanger and normally lying snugly thereon for supporting a propeller shaft, an-anchorage ring carried by said bearing plate,

'said ring having ears formed thereon, and an elastic band threaded through said apertures in said hanger and extending over said ears for flexibly supporting said bearing plate in proper alignment'with respect to said hanger.

2 A hearing for a model airplane shaft comprising a hanger, said hanger having a plurality of apertures formed: therein, a bearing fplate mounted upon said hanger and normally lying snugly thereon for supporting a propeller shaft,- an anchorage ring carried by saidbearing-Dlate, said ring having ears "formed thereon,:and:an elastic band threaded'through said apertures in said hanger and extending over said ears for flexibly supportingsaid bearing plate ,in proper alignment with respect to said hangen said-ears being formed upon the periphery of said anchorage ring and being forwardlyextended and in- Wardly inclined. V I a 3. In combination with a motor, stick, of a bear: ing for a model airplane shaft comprising a hanger member embodying a right-angularstructure provided with an elongated finger for facilitating the securing of the hanger member tosaidmotor having an aperture extending-substantially centrally thcrethrough, a bearing having an extended bushing seated in saidaperture, said front'plateand flanges having apertures formed therein, an. anchorage ring carried by said-bearing and having projecting tongues and a flexible band passing through said last mentioned.- apertures and engaging saidtongues for flexibly supporting said bearing in engagement with said hanger.

4-. vIn a model airplane, a propeller shaft, a support for said propeller shaft, 2. motor for said. propeller shaft, and elastic anchorage means for anchoring said shaft support against rotation and permitting said support to flex, said-elastic anchorage means being independent .of said motor;

5. In a model airplane, a'propeller shaft, a bearing, a support for said bearing, a motor for. said shaft, and means for resiliently anchoring said bearing upon said support for normally maintainingthe thrust line=cf the propeller-uniform relative to said support irrespective of the operation of-the motor,

6. In amodel airplane, -a propeller "shaft, a bearing for said propeller'shaft, a support for said bearing an elastic motor for driving said.

'7. A-mounting for a modelairplane propeller comprisinga support, a propeller shaft, a bearing for said propeller shaft, and resilient means, d1" rectly engaging. said bearing and resiliently'hold-.

ing said bearing in engagement withsaid-sup- I port, I

-8. A mounting for a model airplane propeller comprising a support, a propeller shaft,a bearing for said propeller shaft, and an elastic band directly engaging said bearing and resiliently-holding said bearing in engagement with said support.

RALEIGH; TL 

